1. Field of the Invention
The present invention relates to a three-dimensional X-ray CT apparatus, a three-dimensional CT image reconstruction method, and a program, and more specifically, to an apparatus capable of displaying a three-dimensional CT image a plurality of times based on data on a plurality of transmission images taken in succession.
2. Description of the Related Art
There have conventionally been known X-ray computer tomography (hereinafter referred to as CT) apparatus, which are capable of non-destructive internal measurement and are used not only to a living organism such as a human body and a laboratory animal but also to examination of an internal structure of a product in general, which is a non-living material. Of the X-ray CT apparatus, compared to a two-dimensional X-ray CT apparatus of a step-scan type, helical-scan type, or the like, a three-dimensional X-ray CT apparatus may acquire a three-dimensional image of a subject. The three-dimensional X-ray CT apparatus, which uses an X ray in a shape of a cone beam, irradiates the subject with the X ray, which forms the cone beam, from an X-ray source and detects the X ray that has transmitted through the subject with a two-dimensional detector. The X-ray source and the two-dimensional detector are rotated with respect to the subject to take a plurality of transmission images. Note that, there is also a case where the X-ray source and the two-dimensional detector are fixed and the subject is rotated. A computer included in the three-dimensional X-ray CT apparatus reconstructs a three-dimensional CT image (volume) based on data on the plurality of taken transmission images to display the three-dimensional CT image. A method for the reconstruction of the three-dimensional CT image is disclosed in, for example, JP 2007-117740 A1.